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Objectives: The purpose of this research was to examine the influence of enamel matrix proteins (EMP) on the viability, proliferation, and attachment of periodontal ligament fibroblasts (PDLF) to diseased root surfaces., Materials and Methods: Primary cell cultures of PDFL were obtained from clinically healthy third molars or premolar teeth. Viability and proliferation rates were carried out over a 10-day period. A total of 80,000 cells were plated in 24-well plates followed by EMEM with 10% FBS (positive control) and EMEM plus EMP at 25, 50, 75, and 100 micro g/ml. Cells were harvested on days 1, 3, 5, 7, and 10 and viability was performed utilizing an MTS assay. PDLF proliferation rates were assessed by a CyQUANT GR dye assay. SEM analysis was used to examine the qualitative effects of cellular attachment to diseased root surfaces following EMP compared to nontreated controls., Results: The results indicated that viability was negatively affected for higher doses over time while lower doses displayed viability effects similar to control. Proliferation, however, appeared to be ameliorated following exposure to EMP. The SEM analysis suggests that cellular attachment to diseased dentin was enhanced following EMP application., Conclusion: These in vitro studies support the concept that EMP may act as a suitable matrix for PDLF.

Treatment planning is a critical aspect of clinical education in the dental school curriculum. It is surprising, therefore, that so little attention has been given to this subject in the dental literature. The importance of treatment planning is reinforced in the standards and the tests that clearly present methods and necessity for treatment planning. However, there is minimal evidence about how these treatment planning courses have been evaluated, how they were incorporated into the curriculum, or how they have been integrated into treatment planning in the academic clinical setting. The purpose of this study was to survey and profile current treatment planning processes in U.S. dental schools. A questionnaire consisting of twenty-nine items relating to treatment plan preparation, process, and outcomes was mailed to fifty-four U.S. dental schools. The primary topics included patient assignments, treatment planning, plan sequencing, plan presentation, informed consent, and plan modifications. Forty-seven of the fifty-four U.S. dental schools (87 percent) completed and returned the surveys. Profiling the treatment planning process in dental schools reveals many similarities. Typically, the schools screen patients prior to assignment to students and expect the student diagnostician to complete the planning process as well as comprehensive care. The patient's welfare is the primary determinant of the content of the plan in 92 percent of U.S. dental schools. Secondly, though current accreditation standards are concentrated on competencies, the treatment plans are influenced by quantitative requirements. Third, the plan is usually completed during the second patient visit after screening. Fourth, the approaches vary among the schools when a multidisciplinary or complex treatment plan is appropriate. Some depend on a panel of experts, whereas others do not have interactive planning with specialists. A significant number of schools decentralize treatment planning and delegate part of the plan to disciplines or group practice leaders. Fifth, the treatment plans and treatment risks are presented in accordance with the intent of the accreditation guidelines; however, fewer than half the schools explain the risk of procedures to patients at the time of plan presentation. Finally, plans change frequently, but the modifications are generally considered to be minor.

Observer reliability in performing linear measurements between the cementoenamel junction and alveolar crest was determined for mandibular posterior teeth from digitized clinical bitewing radiographs acquired during recall examinations. 6 measurements (corresponding to traditional probing measurements) were made per tooth by 3 observers. Mesial and distal measurements made to the most coronal aspects of the alveolar crest were the most reliable and least biased. As was anticipated, intra-observer reliability was better than inter-observer reliability although the 3 observers of our study were able to detect a significant mean change (0.1 mm, p<0.0001) in alveolar bone height over a 1-year period for 10 patients. For our most reliable and unbiased measurements (mesial measurements to the alveolar crest), a change of 0.54 mm (90th percentile) would be required to indicate change at a site from one time to the next. Based on the reliability of our digital radiographic measurements, with the alpha error rate set at 0.05 and beta at 0.20, a difference in alveolar bone height of 0.3 mm could be detected with a patient sample size of between 13 (best case) and 54 (worst case).

To determine whether postmenopausal bone loss and factors associated with osteoporosis affect tooth retention, we examined vertebral and proximal femoral (postcranial) bone mineral density in relation to tooth loss and attachment loss in a cross-sectional study of 135 postmenopausal women (age range 41-70 yr). Women had at least 10 teeth and no evidence of moderate or severe periodontal disease. Full-mouth attachment loss measurements were made using a pressure-sensitive probe, and bone density was determined by dual-energy X-ray absorptiometry. Attachment loss was correlated with tooth loss (number of remaining teeth, radiologically determined), but not with vertebral or proximal femur bone density. Multivariate analysis showed current smoking (p = 0.01), years since menopause (p = 0.02) and the interaction of age and current smoking (p < 0.01), to be statistically significant predictors of attachment loss in our study population.

In vitro periodontal alveolar bone mineral content (BMC) measurements obtained with dual-energy radiography (DER) were compared with assessments based on bitewing radiographs (BWX). In addition, in patients, the relationship between bitewing and several postcranial dual-energy-radiographic measures were evaluated. Dual-energy-radiographic and bitewing measurements were made on 2 cadaver mandibles initially and after 2 incremental bone reductions at 4 sites. Rank-order correlations between dual-energy-radiographic and bitewing measures for the 4 sites ranged from 0.7 to 1.00. Bitewing measures indicated true bone loss with a sensitivity of 1.00. For patients, correlations between bitewing measures and dual-energy-radiographic scans suggested the strongest relationships were in the distal sections of the radius and ulna and in the intertrochanteric and Ward's areas of the femur. Correlations, in the 0.5-0.6 range, were not statistically significant (p > 0.05), but were quite robust considering the small sample size and preliminary nature of this investigation. Results suggest that the bitewing measure is sufficiently sensitive to detect clinically meaningful (5% or greater) changes in alveolar BMC and, further, that alveolar bone mineral content may reflect postcranial BMC. The implications of postcranial bone mineral changes being reflected in alveolar bone would enhance both our understanding and treatment of alveolar bone loss. The use of bitewing measures to facilitate identification of patients with postcranial bone loss is discussed.

Previous studies have demonstrated that accurate alveolar bone-level measurements can be made using digitally enhanced bitewing radiographs. In this study, we determined the effect of exposure variations on bone-level measurement accuracy using digital radiographic images of dry skulls. 6 direct bone-level measurements on the mandibular 1st molars of dry skulls were established by consensus of 2 expert observers. 13 bitewing radiographs were taken on each side of 11 skulls, using a specially designed positioning device. Exposure settings of 70 kVp, 10 mA, and 24 impulses were empirically chosen as the baseline. Kilovoltage and impulses times were individually varied (50 to 100 kVp in 10 kV increments and 15 to 48 impulses in 6 steps) to ensure a wide range of clinically relevant optical densities on the test images. The radiographs were digitized and alveolar bone level measurements, corresponding to those for skulls, were made on the images by 2 observers. Pearson product-moment coefficients between radiographs and criteria measurements were calculated. It was found that dry skull and digital bitewing radiographic measurements were highly correlated, within the limits of exposure parameter variations tested. Accurate measurements of alveolar bone level are possible from bitewing radiographs taken within a wide range of exposures, when digital image processing techniques are employed.

Alveolar bone loss measurements made using digitized dental radiographs have been shown to be precise and accurate. We determined the influence of alignment errors introduced when exposing the radiographs on the precision and accuracy of bone loss measurements. Bitewing radiographs of 15 day skulls were obtained using a positioning device (modified after the methods of Duckworth and associates). The sequence of radiographs was taken while the alignment of the main Roentgen beam was systematically varied within a 10 degree cone. Angular displacements were calculated from the digitized radiographs. Space variant digital image enhancement was performed to improve visualization of the cementoenamel junctions and alveolar crests. Corresponding bone loss measurements were made on dry skulls and radiographs. The criterion for truth in these measurements was established by 2 expert observers who measured the skulls with periodontal probes. Radiographic measurements were statistically compared with the criterion using validity coefficients. We found beam positioning errors of up to 10 degrees do not substantively affect alveolar bone loss measurements of mandibular molars taken from enhanced digital images of bitewing radiographs.

Many physical anthropological studies require that an observer or device discriminate between states that can be easily confused. Receiver operating characteristic (ROC) analysis currently offers the best method for determining the accuracy of such choices, particularly for small sample sizes. Although ROC analysis is widely accepted in psychophysical and biomedical testing, its use in anthropological studies has not been reported. ROC analysis is used here to determine the usefulness of enhanced dental radiographs to assess vertical alveolar bone defects for quantitative studies of human variation with regard to periodontal disease. The presence or absence of vertical-bony defects (truth) for 75 human skulls was established by the consensus of two trained observers. Dental bitewing-radiographs were taken of the alveolar processes, the radiographs digitized, and the brightness and contrast of the digital images enhanced. The two observers who established truth then rated 1) plain bitewing radiographs, 2) unenhanced digital images of bitewings, and 3) enhanced digital images of bitewings for vertical bony defects. The rating scale varied from 1 (vertical defect definitely or almost definitely present) to 5 (definitely or almost definitely absent). ROC analysis was used to compared the diagnostic value of the 3 imaging modalities. All modalities had nearly identical diagnostic performance, measured as Az values (areas beneath ROC curves) that were less than 0.80, which indicates only moderate usefulness. It is concluded that enhancement does not increase success in vertical-bony-defect diagnosis from digital dental radiographs processed in this manner. Moreover, it is suggested that conventional bitewing radiographs may be unsuitable for accurate quantification of such defects.